Q: Is mutilate still good after the hotfixed nerf to HfB?
A: Yes, Mutilate was a good 10% ahead of everyone else on singletarget. After the change Mutilate will still be king on singletarget throughout normalmodes, but Combat is likely to be better for certain fights. There's now an interresting choice between Combat and Mutilate which is what the game is about. Combat surpasses Mutilate even on singletarget once you start getting ilvl277 gear, mainly due to Arp scaling and badly itemized Mutilate gear.

Q: When do I choose between A1 and A2?
A: If you have gear of ilvl 232 or below, use A2. If you have T9 gear better than that use A1. If you have better than T9 gear and really high crit rating, visit a spreadsheet and make sure you aren't crit capping. If you are, Opportunity Mutilate is most likely better. 4T10 favors A2, but it doesn't mean it's always better than A1 if you're wearing 4T10.

Q: Isn't 2 points in Opportunity better than 2 points in RS? Isn't Quick Recovery/Vigor better than Fleet Footed?
A: No. Some fights such as Lich King or Saurfang heroic may warrant one point in Deadly Brew for the free-of-cost slow however.

Q: Where do I find these spreadsheets?
A: In the stickies and directly at Elitist Jerks http://elitistjerks.com/f78/. Also, there's no excuse for not being able to use those spreadsheets, they're _that_ simple. Since they are that simple, please don't pester the EJ forum with some question you could just as easily ask here or work out in 5 minutes if you actually bothered.

Q: What weapons should I use and where does my poisons go?
A: Same as always, highest DPS in the mainhand.
Slow/Fast: MH Instant & OH Deadly. Fast/Fast: OH Instant & MH Deadly.
e: There's some evidence tthat suggest Fast/Slow may eventually become better: http://elitistjerks.com/f78/t51426-depth_mutilate_cycle_analysis/p11/#post1510284
e: Using Taiaj favors a slow mainhand so that you should go slow/fast at equal dps daggers. Without going into details this is because Manifest Anger is performed by either you main- or offhand with a distribution that reflects the speed difference of the weapons.

Q: Glyphs?
A: HfB+Mutilate+FoK/Tricks

Q: But Tricks costs me energy and DPS
A: That's not a question and you're not a good rogue. Use it. Every cooldown. Thanks.

Q: How do I play Mutilate?
A: Use Mutilate till you have 4 or more cp - we denote this as the 4+ cycle. Use Envenom when you have enough energy and try not to clip the Envenom buff. 3+ cycles can be used to stack up Deadly Poison when swapping targets.

Q: What does clip the Envenom buff mean?
A: It means pressing Envenom while the 5-6 seconds buff from your previous Envenom is still active.

Q: I hear energy pooling is really pro, is it?
A: Short answer: no. Longer answer: sometimes very much no, but Envenom buff time plays a part aswell, so it can be if executed properly. You should still pool energy in order not to clip Envenom, but don't let your energy cap out. The spreadsheet's !calcs tab has a row called "max pool size" which you should pay attention to.

Q: So how do I execute energy pooling properly?
A: Make sure not to pool more than 60 energy unless you really know what you're doing ("max pool size") and do it to maximize the Envenom buff uptime during trinket procs.

Q: So how do I track all this stuff like a pro?
A: Eventhorizon. Learn to love it. There's plenty of guides to get you started on the addon's page at wowinterface.
What you need to track is this:

Q: What about Need to Know or RPB or Rogue HUD or or or?
A: Sure, I still believe Eventhorizon is best though. It condenses alot of information on a very small space both in terms of memory and screen usage. You wouldn't drive a Hummer in a car race either would you? Rogue HUD is amazing if you can be bothered to set it up though.

Q: But what about Rupture?
A: If you have gear of ilvl 245 or better: no. If you have 4T8: yes. If neither of those apply: visit a spreadsheet.

Q: What gems should I use?
A: This will depend HEAVILY on your gear. You're gonna want to be expertise capped. Once that is sorted, you should check if you're crit capped or hitting the crit cap during trinket procs. If you are, you need to socket HIT in yellow sockets. If not, socket HASTE or AP/HASTE to such a degree that your HASTE ep value is near 2.
In your red sockets you'll be using EXPERTISE up to the cap and either AP or AP/HASTE after that - consult a spreadsheet and check what's best in your situation.

Q: What do I do if I have noone to put up a bleed debuff for me?
A: You use Rupture instead of Envenom every now and then when HfB is about to run out.

Q: How do I open on a boss?
A: However you please, really.

Q: Is Imp.SnD any g...?
A: No.

Q: My AoE is really awfull, help me please?
A: Yes, it is. The poison change did nothing to help AoE damage.
The easy way is to spec Combat. Similarly it's probably worth asking; how many arcane mages du you see on Anub'arak/Lich King heroic for instance?
Mutilate FOK is only decent on a high number of targets. You can put out some decent burst on trash by making sure Overkill is up and Envenom->FOK, but it'll rarely ever be able to compete with Blade Flurry+Vitality.

Q: My DPS is horribad when I need to swap targets, what am I doing wrong?
A: This isn't Combat. There's some amount of ramp up time to Mutilate DPS. This is the primary reason Combat was superior to Mutilate in Coliseum despite being worse for single target dps.
You're gonna want to know the fight specifics and time your energy and Envenoms accordingly. To use a known example, having a near full energy bar with 4+cp on Jaraxxus will give you very respectable dps on the portal if you use Envenom just before switching targets.
That said if you learn how to swap targets as Mutilate, it can be better than Combat. It doesnt have BF though, which is a huge setback in such situations.

Q: So Combat isn't completely dead?
A: Very much no. At the very least, it's still alot better for AoE and whenever you need to swap targets or burn down a partcular mob to win the fight - think Jaraxxus portal.

Q: When do I use Vanish to start Overkill?
A: Whenever you'd look the most like Neilyo. If there's nothing fight specific that can be avoided through Vanish, use it as soon as possible.

Q: What trinkets should I use?
A: Anything but ARP trinkets. The one from Emblems of Frost is amazing, so is Comet's Trail. DC(heroic) is good atm, but may eventually cause you to crit cap. BIS is some combination of Taiaj+HWT+WFShc depending on your gear.

Q: So what is crit cap?
A: It's an expression to describe the situation where all your hits are crits and then some.
The formula for determining your crit cap is 100-M-D-G.
The technical explanation is you're pushing hit completely off the hit table effectively wasting every additional point of crit you'd gain. When you hit a target, the game rolls 1-100 (actually there's 2 rolls in some situations, but let's forget that for now). Depending on what it rolls, a particular kind of hit will occur. Lets say I raidbuffed have 24% chance to get a Glancing Attack, 1% chance to be Dodged, 0% chance to be Parried (I'm behind the boss), and a 15 % chance to miss. This would make my hit table look like this:
1-15: Miss
16: Dodge
17-40: Glancing
40-45: Forced Crit Depression
45-100: Hit and Crit
As you can see I have 60% to Hit or Crit. If my Crit Chance goes above 60%, we say I'm at the hard crit cap. If I go above 60% with a trinket proc, I'm at the soft crit cap. You cannot gear crit to counter the forced crit depression. If you have 60% chance to crit you'll see 4.8% hits despite being at the cap.
Notice how your crit cap will depend on your hit rating and your expertise rating.
See http://elitistjerks.com/f31/t76785-crit_depression_combat_table/

Q: I don't get that.
A: Again, not a question, but OK. Visit a spreadsheet. If something glows red, you're in trouble with the crit cap.

Q: So what profession is best?
A: http://forums.wow-europe.com/thread.html?topicId=12947241910&postId=129459887311&sid=1#5

Q: What race is best?
A: Depends entirely on the fight. If you're alliance the correct answer is "whatever makes sure you have a pocket squid". See http://forums.wow-europe.com/thread.html?topicId=11155640973&sid=1#4

Q: How good is the Kirin Tor ring?
A: Compared to what is available pre ICC it's 2nd BiS. There's some fairly easily obtainable rings in the first area though.

Q: What should I spend my Emblems on?
A: The difference between T9 and 2 pieces of the 10man T10 set is pretty much the same as the gain from DMC to Harkumi War Token. If you want to be sure, visit a spreadsheet.

Q: Mongoose?
A: Mongoose was good when it procced 2% haste. This is nolonger the case as it now procs haste rating, making it useless for raiding at lvl80.